This invention relates to catheterization and more particularly, to catheterization in which the possibility of internal injury to the patient is mitigated or avoided.
A catheter is a tubular instrument that is inserted into a passageway for a wide variety of actual and potential uses. One such use is the drainage of urine when natural discharge is impeded or prevented. Another use, provided by, the Eustachian catheter, entry to the middle ear for inspection or medical prosthesis.
Catheters are typically designed with a special tip that is inserted into a body cavity, such as the bladder. The tip communicates with an external end of the catheter tube through a hollow, elongated interior. This allows such functions as drainage, removal or inspection. For urine drainage, the most commonly used tube is the Foley cathether, named for its inventor.
In order to assure proper placement and retention of the catheter within the body, an annular, inflatable portion is spaced inwardly from the tip. The annular portion is normally deflated. It is inflated after insertion of the tip into the body, for example, the urinary bladder. The external end of the catheter also is provided with a branch arm by which the desired inflation can take place. For that purpose the branch arm includes a one-way valve through which fluid (water or air) can be admitted under pressure to the inflatable annular portion. This takes place through a narrow, elongated passageway extending substantially parallel to the main elongated and hollow cylindrical interior of the catheter tube.
By the introduction of either water or air under pressure into the branch arm, the annular portion of the catheter, when inflated, assumes a substantially toroidal shape. When a Foley catheter is inserted into the urinary bladder, the inflated annulus retains the tip of the catheter at the entrance of the bladder. This assures proper drainage through the opening provided in the catheter tip, and then through the hollow interior of the catheter to, for example, a waste container. Such a container may be strapped or otherwise affixed to the patient, typically at or above the knee.
The patient, or visitor, may accidentally step upon the waste container, or the waste container may become lodged or snagged, causing the Foley catheter to be pulled outwardly. In other cases the attendant removes the catheter by an excessive tug, or the patient withdraws it with a forceful tug.
With its toroidal portion fully inflated, the pulling or dislodging of a Foley catheter from the urinary bladder, and through the urethra, can cause severe lacerations and pain. In some cases there is severe bleeding and possible damage to the external urinary sphyncter, resulting in permanent urinary incontinence.
In other cases the catheter may be forcefully pulled from the patient because of a mistaken belief that the balloon of the catheter has been disinflated. Once again there is a possiblity of serious injury to the patient.
In an attempt to alleviate the damage that can be caused by premature catheter removal, the prior art of U.S. Pat. No. 3,951,153 provides a coupler for Foley catheters.
The coupler is positioned at an external location intermediate the ends of the catheter. It is adapted to enable a section of the catheter to become relatively easily and rapidly disconnected from the section of the catheter with the inflated balloon within the urinary bladder.
This disconnection is supposed to occur if the section of the catheter joined to the waste container is either accidentally or deliberately displaced from the remaining section. The disconnection is to prevent the remaining section from being drawn out of the urinary bladder to avoid laceration of the urinary canal, severe bleeding, possible urinary incontinence, and attendant pain.
The coupler of U.S. Pat. No. 3,951,153 is a circular shaped flange which is notched to anchor strips the severed end of the catheter, with the insertable tip firmly positioned, to form a water or air-tight seal for the passageway leading to the inflated toroid of the catheter. This allows the torroid to remain in its inflated position. The portion of the catheter joined to the waste container is force fitted on an oppositely directed, hollow cylindrical projection. This enables the section of the catheter joined to the waste container to be released from the coupler if either an accidental or deliberate force pulls this portion of the Foley catheter away. The portion inserted into the urinary bladder remains in position, preventing lacerations of the urinary canal, and such severe complications as bleeding and permanent urinary incontinence.
Unfortunately, the separate portions of the catheter in accordance with U.S. Pat. No. 3,951,153 do not always release as intended. In addition, there is the need for a special coupler, and the futher need to sever and slit the severed ends of the catheter.
It is therefore an object of the invention to provide for catheterization that facilitates catheter release when a pull is entered upon an inserted catheter with an inflated balloon. A related object is to prevent disastrous lacerations of the urinary canal. Another related object is to maintain a tight seal for the passageway used to inflate the inflatable portion.
Another object is to achieve release in the event that the portion of the catheter joined to a waste container is either deliberately or accidentally disturbed.
A further object of the invention is to overcome the shortcomings associated with U.S. Pat. No. 3,951,153, since the portions of the catheter in accordance with that patent do not always release as intended. A related object is to avoid the complication of requiring a special coupler, and the futher complication of the need to sever and slit one of the severed ends of the catheter.